Variable intraspecific response to climate change in a medicinally important African tree species, Vachellia sieberiana (DC.) (paperbark thorn).

Climate change is predicted to disproportionately impact sub-Saharan Africa, with potential devastating consequences on plant populations. Climate change may, however, impact intraspecific taxa differently. The aim of the study was to determine the current distribution and impact of climate change on three varieties of Vachellia sieberiana, that is, var. sieberiana, var. villosa and var. woodii. Ensemble species distribution models (SDMs) were built in "biomod2" using 66, 45, and 137 occurrence records for var. sieberiana, var. villosa, and var. woodii, respectively. The ensemble SDMs were projected to 2041-2060 and 2081-2100 under three general circulation models (GCMs) and two shared socioeconomic pathways (SSPs). The three GCMs were the Canadian Earth System Model version 5, the Institut Pierre-Simon Laplace Climate Model version 6A Low Resolution, and the Model for Interdisciplinary Research on Climate version 6. The suitable habitat of var. sieberiana predominantly occurs in the Sudanian and Zambezian phytochoria while that of var. villosa largely occurs in the Sudanian phytochorion. The suitable habitat of var. woodii mainly occurs in the Zambezian phyotochorion. There is coexistence of var. villosa and var. sieberiana in the Sudanian phytochorion while var. sieberiana and var. woodii coexist in the Zambezian phytochorion. Under SSP2-4.5 in 2041-2060 and averaged across the three GCMs, the suitable habitat expanded by 33.8% and 119.7% for var. sieberiana and var. villosa, respectively. In contrast, the suitable habitat of var. woodii contracted by -8.4%. Similar trends were observed in 2041-2060 under SSP5-8.5 [var. sieberiana (38.6%), var. villosa (139.0%), and var. woodii (-10.4%)], in 2081-2100 under SSP2-4.5 [var. sieberiana (4.6%), var. villosa (153.4%), and var. woodii (-14.4%)], and in 2081-2100 under SSP5-8.5 [var. sieberiana (49.3%), var. villosa (233.4%), and var. woodii (-30.7%)]. Different responses to climate change call for unique management and conservation decisions for the varieties.

One Health monitoring reveals invasive freshwater snail species, new records, and undescribed parasite diversity in Zimbabwe.

BACKGROUND: Snail-borne trematodes afflict humans, livestock, and wildlife. Recognizing their zoonotic potential and possible hybridization, a One Health approach is essential for effective control. Given the dearth of knowledge on African trematodes, this study aimed to map snail and trematode diversity, focusing on (i) characterizing gastropod snail species and their trematode parasites, (ii) determining infection rates of snail species as intermediate hosts for medically, veterinary, and ecologically significant trematodes, and (iii) comparing their diversity across endemic regions. METHODS: A cross-sectional study conducted in 2021 in Chiredzi and Wedza districts in Zimbabwe, known for high human schistosomiasis prevalence, involved malacological surveys at 56 sites. Trematode infections in snails were detected through shedding experiments and multiplex rapid diagnostic polymerase chain reactions (RD-PCRs). Morphological and molecular analyses were employed to identify snail and trematode species. RESULTS: Among 3209 collected snail specimens, 11 species were identified, including schistosome and fasciolid competent snail species. We report for the first time the invasive exotic snail Tarebia granifera in Zimbabwe, which was highly abundant, mainly in Chiredzi, occurring at 29 out of 35 sites. Shedding experiments on 1303 snails revealed a 2.24% infection rate, with 15 trematode species identified through molecular genotyping. Five species were exclusive to Chiredzi: Bolbophorus sp., Schistosoma mansoni, Schistosoma mattheei, Calicophoron sp., and Uvulifer sp. Eight were exclusive to Wedza, including Trichobilharzia sp., Stephanoprora amurensis, Spirorchid sp., and Echinostoma sp. as well as an unidentified species of the Plagiorchioidea superfamily. One species, Tylodelphys mashonensis, was common to both regions. The RD-PCR screening of 976 non-shedding snails indicated a 35.7% trematode infection rate, including the presence of schistosomes (1.1%) Fasciola nyanzae (0.6%). In Chiredzi, Radix natalensis had the highest trematode infection prevalence (33.3%), while in Wedza, R. natalensis (55.4%) and Bulinus tropicus (53.2%) had the highest infection prevalence. CONCLUSIONS: Our xenomonitoring approach unveiled 15 trematode species, including nine new records in Zimbabwe. Schistosoma mansoni persists in the study region despite six mass deworming rounds. The high snail and parasite diversity, including the presence of exotic snail species that can impact endemic species and biomedically important trematodes, underscores the need for increased monitoring.

Integrated chronic care models for people with comorbid of HIV and non-communicable diseases in Sub-Saharan Africa: A scoping review.

BACKGROUND: Integrated health care is an approach characterized by a high degree of collaboration and communication among health professionals. Integration of HIV/NCD is recommended to enhance the quality of healthcare services being provided. Duplication of limited resources is minimized, and a holistic care approach is promoted by shifting from acute and reactive care to care that embraces patient-centredness that includes promotive health and disease surveillance. The high burden of HIV disease in sub-Saharan Africa (SSA) combined with the increasing prevalence of chronic non-communicable diseases (NCDs) necessitates a review of how health systems has been doing to deliver quality integrated care for people living with HIV (PLWH) and comorbid chronic NCDs. METHODS: A scoping review was conducted to identify and describe all publications on integrated chronic care management models at the primary care level in the SSA context, particularly those that addressed the care of PLHIV with co-morbid chronic NCDs. The inclusion and exclusion criteria were applied, and duplicates were removed. RESULTS: A total of twenty-one articles were included in the final review. Integrated healthcare systems were reported in only eight SSA countries-(South Africa, Uganda, Kenya, the United Republic of Tanzania, Zambia, Malawi, Zimbabwe and Swaziland). Integrated care systems adopted one of three health models. These included added-on NCD services to previously dedicated HIV care facilities, expansion of primary care facilities to include HIV care and establishment of integrated care services. Short-term benefits included staff capacitation, improved retention of patients and improved screening and detection of NCDs. However, the expansion of existing services resulted in an increased workload with no additional staff. A significant positive change noted by communities was that there was less or no stigmatisation of people living with HIV when attending dedicated HIV clinics. CONCLUSION: Evidence of integrated healthcare services for PLWH and co-morbid of NCDs in SSA is scanty. Data on some short-term benefits of integrated care was available, but evidence was absent on the long-term outcomes. Randomized clinical trials with clearly defined comparator groups and standardized measures of HIV and NCD outcomes are needed to demonstrate non-inferiority of integrated against non-integrated care.

Diabetes mellitus and associated factors among HIV-positive patients at primary health care facilities in Harare, Zimbabwe: a descriptive cross-sectional study.

BACKGROUND: Highly active antiretroviral therapy (HAART) has improved the life expectancy of people living with HIV (PLWH) and has increased the risk of chronic non-communicable diseases. Comorbid HIV and diabetes mellitus (DM) significantly increase cardiovascular disease and mortality risk. This study aimed to determine the prevalence of type 2 diabetes mellitus among HIV-positive patients receiving HAART in Zimbabwe and its associated risk factors. METHODS: This cross-sectional study was conducted at eight primary healthcare facilities in Harare, Zimbabwe, between January 2022 and March 2023. Non-probability convenience sampling was used to recruit adult HIV-positive patients undergoing HAART attending the facilities. Data were captured on clinical history and socio-demographic and behavioral characteristics, and analyzed using descriptive statistics to determine DM prevalence rates. Additionally, bivariate and multivariate logistic regression models were employed to examine factors associated with HIV and DM comorbidities. RESULTS: A total of 450 participants were included in this study, of which 57.6% (n = 259) were female. The majority were married (73.8%) and older than 35 years (80.2%). Most participants had completed high school (87.6%) and 68.9% were employed either formally or self-employed. The prevalence of diabetes mellitus (DM) was 14.9%. HIV/DM comorbidity was more prevalent in patients who were female, self-employed, and smoked (p < 0.05). Multivariate logistic regression analysis revealed that the factors associated with DM-HIV comorbidity were gender, age, education, marital status, employment status, smoking, physical activities, duration of HAART, and diet. Age, level of education, marital status, and occupation were not associated with HIV-DM comorbidity. Obesity (body mass index > 30 kg/m2), smoking, and alcohol consumption were associated with an increased risk of DM. Regular physical activity is associated with a reduced risk of DM. CONCLUSION: A substantial burden of DM was found in PLWH. The intersectoral integration approach is advocated, and active screening for DM is recommended. Gender-specific interventions are necessary to target diseases and health behaviors that differ between men and women. These interventions should be customized to the specific diseases and behaviors of each group.

Effects of temperature on the life history traits of intermediate host snails of fascioliasis: A systematic review.

BACKGROUND: The impact of climate change has led to variations in various biological processes, leading to altered transmission dynamics of infectious diseases, including snail-borne diseases (SBDs). Fascioliasis is one of the neglected zoonotic tropical snail-borne diseases caused by the trematode of the genus Fasciola. This review focused on laboratory experimental and model studies that evaluate the potential effect of temperature change on the ecology and biology of the intermediate host snails (IHS) of Fasciola. METHODS: A literature search was conducted on Google Scholar, EBSCOhost, and PubMed databases using predefined medical subject heading terms, Boolean operators, and truncation symbols in combination with direct keywords: Fasciolosis AND Temperature, Lymnaea OR Austropeplea OR Radix OR Galba OR Fossaria OR Pseudosuccinea AND growth, fecundity, AND survival at the global scale. Other search terms used were (Fascioliasis AND Temperature), (Lymnaea AND Temperature), (Austropeplea AND Temperature), (Fossaria AND Temperature), (Galba AND Temperature), (Pseudosuccinea AND Temperature), and (Radix AND Temperature). RESULTS: The final synthesis included thirty-five published articles. The studies reviewed indicated that temperature rise may alter the distribution, and optimal conditions for breeding, growth, and survival of IHS, ultimately resulting in changing the transmission dynamics of fascioliasis. The literature also confirmed that the life history traits of IHS and their interaction with the liver fluke parasites are driven by temperature, and hence climate change may have profound outcomes on the population size of snails, parasite density, and disease epidemiology. CONCLUSION: We concluded that understanding the impact of temperature on the growth, fecundity, and survival of IHS may broaden our knowledge of the possible effects of climate change and hence inform fascioliasis control programs.

Barriers and Facilitators of Adherence to Oral Anticancer Medications Among Women with Breast Cancer: A Qualitative Study.

Purpose: Despite the life-saving benefits of oral anticancer medications (OAMs) to women with breast cancer (BC), adherence remains suboptimal and, in many cases, not well documented. The study examined barriers and facilitators of adherence to OAMs among women receiving BC treatment in Nigeria. Patients and Methods: The study was framed within the World Health Organization (WHO) Multidimensional Model of Adherence. We conducted qualitative in-depth interviews of 16 purposively sampled women in two tertiary hospitals in Southern Nigeria. The interviews were audio-recorded and transcribed verbatim. The interview data were analyzed using the Framework Method. Results: The key barriers to OAM adherence mentioned were socioeconomic factors (high cost of medication) and therapy-related factors (medication side effects). The key facilitating mechanisms for adherence to OAMs mentioned included; (i) patient-related psychosocial factors such as self-encouragement and self-discipline in sticking to the prescription, taking the medication at a particular time each day, receiving practical support from family members; and (ii) healthcare team/system factors such as obtaining an adequate supply of the medication at the pharmacy. Conclusion: Barriers and facilitators to OAM adherence are multidimensional. The study findings highlight the potential benefit of a multifaceted intervention (such as patient education and monitoring or strategies promoting cost-containment and side effects management) to optimize adherence. Therefore, our findings may inform the designing and evaluating of context-specific adherence measures and multifaceted intervention strategies targeting key barriers and approaches that enable adherence to enhance patient outcomes.

Infection Rates of Fasciola Intermediate Host Snail Species and Their Distribution in Africa: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis aimed to collate the infection rates of Fasciola spp. in intermediate host snails and their distribution in Africa. The overall infectivity prevalences of Galba truncatula, Radix natalensis, and Pseudosuccinea columella are 52%, 8%, and 3%, respectively. The intermediate host snails native to Africa (R. natalensis and G. truncatula) have been examined more than the invasive P. columella. The studies included in the review ranged from 1999 to 2022. North Africa has the highest prevalence of G. truncatula, with an infection rate of 52%. The review reveals that naturally infected intermediate host snails (G. truncatula, R. natalensis, and P. columella) are found in various regions of Africa. G. truncatula accounts for 22% (from three countries) of the studies included in the review and it was only found in the North African region with the highest overall infection rate of 52%. More studies on infection rate and distribution are needed to effectively control and prevent future transmissions.

Spatial and seasonal distribution of human schistosomiasis intermediate host snails and their interactions with other freshwater snails in 7 districts of KwaZulu-Natal province, South Africa.

The spatial and seasonal distribution, abundance, and infection rates of human schistosomiasis intermediate host snails and interactions with other freshwater snails, water physicochemical parameters, and climatic factors was determined in this study. A longitudinal malacology survey was conducted at seventy-nine sites in seven districts in KwaZulu-Natal province between September 2020 and August 2021. Snail sampling was done simultaneously by two trained personnel for fifteen minutes, once in three months. A total of 15,756 snails were collected during the study period. Eight freshwater snails were found: Bulinus globosus (n = 1396), Biomphalaria pfeifferi (n = 1130), Lymnaea natalensis (n = 1195), Bulinus tropicus (n = 1722), Bulinus forskalii (n = 195), Tarebia granifera (n = 8078), Physa acuta (n = 1579), and Bivalves (n = 461). The infection rates of B. globosus and B. pfeifferi are 3.5% and 0.9%, respectively. In our study, rainfall, pH, type of habitats, other freshwater snails and seasons influenced the distribution, abundance, and infection rates of human schistosomiasis intermediate host snails (p-value < 0.05). Our findings provide useful information which can be adopted in designing and implementing snail control strategies as part of schistosomiasis control in the study area.

Spatial distribution, abundance, and infection rates of human schistosome-transmitting snails and related physicochemical parameters in KwaZulu-Natal (KZN) province, South Africa.

This study investigated the spatial distribution, abundance, and infection rates of human schistosome-transmitting snails and related physicochemical parameters and environmental factors in 11 districts in KwaZulu-Natal (KZN) province, South Africa, from December 2020-February 2021. Snail sampling was carried out in 128 sites by two people for 15 min using scooping and handpicking methods. Geographical information system (GIS) was used to map surveyed sites. In situ measurements of physicochemical parameters were recorded, while remote sensing was used to obtain measurements for climatic factors required to achieve the study's objective. Cercarial shedding and snail-crushing methods were used to detect snail infections. Kruskal-Wallis test was used to test the differences in snail abundance among snail species, districts, and habitat types. A negative binomial generalized linear mixed model was used to identify the physicochemical parameters and environmental factors influencing the abundance of snail species. A total of 734 human schistosome-transmitting snails were collected. Bu. globosus were significantly more abundant (n = 488) and widely distributed (found in 27 sites) compared to B. pfeifferi (n = 246) found in 8 sites. Bu. globosus and B. pfeifferi had infection rates of 3.89% and 2.44%, respectively. Dissolved oxygen and normalized difference vegetation index showed a statistically positive relationship, while normalized difference wetness index showed a statistically negative relationship with the abundance of Bu. globosus. However, there was no statistically significant relationship between B. pfeifferi abundance, physicochemical parameters, and climatic factors. Our study described the current distribution, abundance, and infection status of human schistosome-transmitting snails in KZN province, which will contribute to informing control measure policies for schistosomiasis.

An assessment on the implementation of same day antiretroviral therapy initiation in eThekwini clinics, KwaZulu-Natal, South Africa.

The World Health Organization (WHO) recommends same-day initiation (SDI) of antiretroviral therapy (ART) for all individuals diagnosed with HIV irrespective of CD4+ count or clinical stage. Implementation of program is still far from reaching its goals. This study assessed the level of implementation of same day ART initiation. A longitudinal study was conducted at four primary healthcare clinics in eThekwini municipality KwaZulu-Natal. Data was collected between June 2020 to October 2020 using a data extraction form. Data on individuals tested HIV positive, number of SDI of ART; and clinicians working on UTT program were compiled from clinic registers, and Three Interlinked Electronic Registers.Net (TIER.Net). Non-governmental organisations (NGO) supporting the facility and services information was collected. Among the 403 individuals who tested HIV positive, 279 (69.2%) were initiated on ART on the same day of HIV diagnosis from the four facilities. There was a significant association between health facility and number of HIV positive individuals initiated on SDI (chi-square=10.59; P-value=0.008). There was a significant association between facilities with support from all NGOs and ART SDI (chi-square=10.18; P-value=0.015. There was a significant association between staff provision in a facility and SDI (chi-square=7.51; P-value=0.006). Urban areas clinics were more likely to have high uptake of SDI compared to rural clinics (chi-square=11,29; P-value=0.003). Implementation of the Universal Test and Treat program varies by facility indicating the need for the government to monitor and standardize implementation of the policy if the program is to yield success.

An assessment on the implementation of same day antiretroviral therapy initiation in eThekwini clinics, KwaZulu­Natal, South Africa

The World Health Organization (WHO) recom mends same day initiation (SDI) of antiretroviral therapy (ART) for all individuals diagnosed with HIV irrespective of CD4+ count or clinical stage. Implementation of program is still far from reaching its goals. This study assessed the level of implementation of same day ART initiation. A longitudinal study was conducted at four primary healthcare clinics in eThekwini municipality KwaZulu Natal. Data was collected between June 2020 to October 2020 using a data extraction form. Data on individuals tested HIV positive, number of SDI of ART; and clinicians working on UTT program were compiled from clinic registers, and Three Interlinked Electronic Registers.Net (TIER.Net). Non governmental organisations (NGO) supporting the facility and services information was collected. Among the 403 individuals who tested HIV positive, 279 (69.2%) were initiated on ART on the same day of HIV diagnosis from the four facilities. There was a significant association between health facility and number of HIV positive individuals initiated on SDI (chi square=10.59; P value=0.008). There was a significant association between facilities with support from all NGOs and ART SDI (chi square=10.18; P value=0.015. There was a significant association between staff provision in a facility and SDI (chi square=7.51; P value=0.006). Urban areas clinics were more likely to have high uptake of SDI compared to rural clinics (chi square=11,29; P value=0.003). Implementation of the Universal Test and Treat program varies by facility indi cating the need for the government to monitor and standardize implementation of the policy if the program is to yield success.

Primary care disaster management for extreme weather events, South Africa.

Primary health care facilities are at the forefront of helping communities affected by natural disasters. However, such facilities are also vulnerable to the effects of extreme weather events triggered by climate change. The April 2022 floods in the south-eastern region of South Africa claimed the lives of over 400 people, the loss of 16 000 houses and resulted in major damage to infrastructure. Most damage was localised in the eThekwini area in KwaZulu-Natal, which is the country's third most populous city. This report describes the impact of the floods on primary health care facilities in eThekwini and their preparedness for extreme weather events.Contribution: Extreme weather events induced by climate change highlight the need for primary health care facilities to develop disaster management strategies that consider climate change.

Engaging youth in stakeholder analysis for developing community-based digital innovations for mental health of young people in Ingwavuma community, in KwaZulu-Natal Province, South Africa.

South Africa faces a critical shortage of mental health service professionals and support for young people with common mental health disorders is inadequate. Social relationships that provide support to adolescents in South African communities are increasingly declining due to socio-economic pressures. Developing ethical digital mental health innovations has potential to address provide services particularly in rural communities where mental health facilities are scarce. The active involvement of young people is critical to maximising uptake and reducing apathy on the use of digital innovations for mental health. Using the nominal group technique this study engaged young people in identifying stakeholders for setting up a community-based mental health intervention in a rural community. Use of nominal group technique for stakeholder analysis proved to a useful tool for engaging young people. The stakeholder identification and analysis provided a base for inclusivity in developing digital innovations for mental health through identifying multi-sector community stakeholders. It revealed that young people in the community have varying perceptions about the level of power and interest which their peers, family members, local leaders, health workers and social development organisations have in developing digital mental health interventions. This research contributes to our understanding of the ways in which to leverage young people's participation in project planning and decision-making and building strong teams and alliances for developing digital innovations for mental health in marginalised rural communities.

Prevalence of Rickettsia africae in tick vectors collected from mammalian hosts in sub-Saharan Africa: A systematic review and meta-analysis.

African tick bite fever (ATBF) is one of the most important rickettsial infections in international travellers to sub-Saharan Africa. The heterogeneity of Rickettsia africae infection rates among tick vector species has been studied. However, this information has not been systematised to allow for comparative estimates. Quantifying the trends and heterogeneity in R. africae infection rates among the different tick vector species is paramount in understanding the role in transmission to humans. A systematic search was conducted in PubMed, Web of Knowledge, Google Scholar, and SCOPUS from 2005 to 2020. The selection criteria included all studies in sub-Saharan Africa reporting R. africae infection rates in tick adults, nymphs, and larvae. A quality effects model was used in the meta-analysis due to the observed heterogeneity with an assessment of publication bias using funnel plots. The prevalence estimates were conducted by geographic region and tick genus from 32 studies reporting R. africae infection rates in ticks from sub-Saharan Africa. A total of 12,301 ticks comprising of adults (96.19%, n=11, 832), nymphs (3.6%, n=443) and larvae (0.2%, n=26) and 1214 pooled samples were evaluated for R. africae infection. The overall prevalence of R. africae was higher in Amblyomma spp. (48%, 95% CI: 26-70%) compared to Rhipicephalus spp. (1%, 95% CI: 0-5%), Hyalomma spp. (1%, 95% CI: 0-3%) and other tick genera (1%, 95% CI: 0-4%) throughout all regions. The highest prevalence in Amblyomma spp. was recorded in western Africa (53%, 95% CI: 14-90%) and in Rhipicephalus spp. in southern Africa (2%, 95% CI: 0-5%). Cattle were the most frequently sampled hosts across all tick vectors (62.98%, n=5492), followed by goats (19.07%, n= 1663) and sheep (9.1%, n= 793). To our knowledge, this is the first systematic and quantitative analysis of R. africae infection in tick vectors collected from mammalian hosts in sub-Saharan Africa. The results highlight a marked heterogeneity between species in different regions of sub-Saharan Africa and provide initial estimates of infection rates.

Human-associated scarcity of hosts for tsetse flies (Diptera: Glossinidae) is related to an increase in prevalence of trypanosome infection in flies in north-eastern Zambia.

Occurrence of nutritional stress (due to depletion of fat reserves) in tsetse flies, associated with inadequate levels of access to blood meals, enhances susceptibility of the flies to trypanosome infection. Thus, in a tsetse-infested area, a spatial gradient of reducing tsetse habitat quality is potentially a gradient of increasing prospects for occurrence of stress in tsetse flies. This study investigated prevalence of trypanosome infection in Glossina morsitans morsitans and G. pallidipes along a transect line hypothesised to represent such a gradient, in relation to the edge of the tsetse belt and distribution of human settlements. This was undertaken in three sites located in Lundazi, Mpika and Rufunsa districts, respectively, in north-eastern Zambia. Human settlement was concentrated at the edge of the tsetse belt in the Mpika and Rufunsa sites and evenly distributed along transect line in the Lundazi site. Tsetse fly samples were collected using black-screen fly rounds and Epsilon traps. Detection of trypanosome infection was by dissection and microscopy in Lundazi and Mpika sites and loop-mediated isothermal amplification (LAMP) test in Rufunsa site. Multiple logistic regression models were applied to determine whether the following factors, 'change in distance from edge of tsetse belt', 'tsetse sampling method' and 'sex of tsetse fly', had effect on 'prevalence of trypanosome infection' in the tsetse flies. Only 'increase in distance from the edge of tsetse belt' for G. m. morsitans was significantly associated with 'prevalence of trypanosome infection' in the flies, in the Mpika and Rufunsa sites. Distance was associated with reduced likelihood of infection with 'one or more subgenera of trypanosomes' and with 'Nannomonas trypanosomes', in the case of 'all sites collectively', 'Lundazi and Mpika sites collectively', Mpika site alone, and Rufunsa site alone. Per site, increase in distance entailed reduced prospects for Trypanozoon infection but only in the Mpika and Rufunsa sites. We conclude that in the Mpika and Rufunsa sites, increase in distance from human settlements entailed reduced likelihood of trypanosome infection, likely due to reducing tsetse habitat degradation, increasing availability of hosts, and hence increasing levels of nutrition and fat reserves, thus enhancing tsetse immunity against trypanosome infection.

Spatial and seasonal distribution of Bulinus globosus and Biomphalaria pfeifferi in Ingwavuma, uMkhanyakude district, KwaZulu-Natal, South Africa: Implications for schistosomiasis transmission at micro-geographical scale.

BACKGROUND: Schsistosomiasis is endemic in sub-Saharan Africa. It is transmitted by intermediate host snails such as Bulinus and Biomphalaria. An understanding of the abundance and distribution of snail vectors is important in designing control strategies. This study describes the spatial and seasonal variation of B. globosus and Bio. pfeifferi and their schistosome infection rates between May 2014 and May 2015 in Ingwavuma, uMkhanyakude district, KwaZulu-Natal province, South Africa. METHODS: Snail sampling was done on 16 sites once every month by two people for 30 min at each site using the scooping and handpicking methods. Snails collected from each site were screened for schistosome mammalian cercariae by the shedding method. The negative binomial generalised linear mixed model (glmm) was used to determine the relationship between abundances of the intermediate host snails and climatic factors [rainfall, land surface temperatures (LST), seasons, habitats, sampling sites and water physico-chemical parameters including pH and dissolved oxygen (DO)]. RESULTS: In total, 1846 schistosomiasis intermediate host snails were collected during the study period. Biompharia pfeifferi was more abundant (53.36%, n = 985) compared to B. globosus (46.64%, n = 861). Bulinus globosus was recorded at 12 sites (75%) and Bio. pfeifferi was present at 7 sites (43.8%). Biompharia pfeifferi cohabited with B. globosus at all the sites it was present. High numbers of Bio. pfeifferi (n = 872, 88.5%) and B. globosus (n = 705, 81.9%) were found between winter and mid-spring. Monthly rainfall showed a statistically significant negative relationship with the abundance of B. globosus (p < 0.05). Dissolved oxygen (DO) had a statistically significant positive relationship with the abundance of Bio. pfeifferi (p < 0.05) while (LST) had a statistically significant negative relationship (p < 0.05). More B. globosus (8.9%, n = 861) were shedding schistosome mammalian cercariae compared to Bio. pfeifferi (0.1%, n = 985) confirming the already documented high prevalence of S. haematobium in Ingwavuma compared to S. mansoni. CONCLUSION: Results of this study provide updated information on the distribution of schistosomiasis intermediate host snails in the study area and contributes towards the understanding of the transmission dynamics of schistosomiasis at the micro-geographical scale in this area.

Effects of Human Settlements and Spatial Distribution of Wing Vein Length, Wing Fray Categories and Hunger Stages in Glossina morsitans morsitans (Diptera: Glossinidae) and Glossina pallidipes (Diptera: Glossinidae) in Areas Devoid of Cattle in North-Eastern Zambia.

The effect of human-associated habitat degradation on tsetse populations is well established. However, more insights are needed into how gradual human encroachment into tsetse fly belts affect tsetse populations. This study investigated how wing vein length, wing fray categories, and hunger stages, taken as indicators of body size, age, and levels of access to hosts, respectively, in Glossina morsitans morsitans Westwood (Diptera: Glossinidae) and Glossina pallidipes Austen (Diptera: Glossinidae), varied along a transect from the edge into inner parts of the tsetse belt, in sites that had human settlement either concentrated at the edge of belt or evenly distributed along transect line, in north-eastern Zambia. Black-screen fly round and Epsilon traps were used in a cross-sectional survey on tsetse flies at three sites, following a transect line marked by a road running from the edge into the inner parts of the tsetse belt, per site. Two sites had human settlement concentrated at or close to the edge of the tsetse belt, whereas the third had human settlement evenly distributed along the transect line. Where settlements were concentrated at the edge of tsetse belt, increase in distance from the settlements was associated with increase in wing vein length and a reduction in the proportion of older, and hungry, tsetse flies. Increase in distance from human settlements was associated with improved tsetse well-being, likely due to increase in habitat quality due to decrease in effects of human activities.

Knowledge and perceptions of schistosomiasis, a water-borne disease, in two semi-arid rural areas of South Africa (Ndumo) and Zimbabwe (Ntalale).

Schistosomiasis is a serious water-borne disease of public health importance in southern Africa and is characterised by high morbidity and negative socio-economic repercussions. Limited knowledge on the mode of transmission and treatment contribute towards increase in the risk of infection. This study assessed community knowledge levels, perceptions and the co-constructed realities of social actors with regards to schistosomiasis in rural resource-poor communities of Ndumo in South Africa and Ntalale in Zimbabwe. We hypothesised that there was association between community knowledge level on schistosomiasis and location of residency and socio-demographic factors. Two-hundred and eight questionnaires were used to gather quantitative data on socio-demographics and knowledge levels while 18 focus group discussions were used to collect qualitative data on perceptions and social constructs. The Fisher's exact and Chi-square tests were used to determine the differences in community knowledge levels based on localities, gender, religion and age. Results showed that awareness level of schistosomiasis was assessed as 'good' in both Ndumo (91%) and Ntalale (81%). Majority of the respondents identified schistosomiasis as a water-borne disease with significantly higher proportion in Ndumo (89%) compared to Ntalale (68%) (p = 0.005). A significant proportion of participants in both localities were aware of the symptoms of schistosomiasis especially the passing of urine with blood (82.5% in Ndumo and 77.0% in Ntalale; p = 0.039). However, presence of schistosomiasis eggs in human stool apart from urine as a sign of infection was highly acknowledged in Ntalale (57.4%) compared to Ndumo (11.7%; p < 0.001). Knowledge on the body parts affected by the infection was low in both localities with 36.9% in Ntalale compared to 1.0% in Ndumo (p < 0.001). In both study areas, local understanding of schistosomiasis was limited to passing urine with blood, a symptom only seen in cases of urinary schistosomiasis. All the participants associated schistosomiasis with being water-borne, but had divergent perceptions on the symptoms, lifecycle and treatment of the infection. Trends of schistosomiasis and at-risk populations were perceived differently in Ndumo and Ntalale. Although respondents from the two localities acknowledged schistosomiasis as water-borne disease, the study showed lack of in-depth knowledge on the life cycle of the diseases. We therefore recommend that health education be implemented together with other strategies such as improvement in access to water and sanitation in the two study areas to achieve effective control and prevention of the disease.

Genetic diversity of Biomphalaria pfeifferi, the intermediate host of Schistosoma mansoni in Shamva district, Zimbabwe: role on intestinal schistosomiasis transmission.

The fresh water snail Biomphalaria pfeifferi is the intermediate host for Schistosoma mansoni, which causes human intestinal schistosomiasis in Zimbabwe. Despite the medical importance of this intermediate host, there are no current data on its molecular characterization in Zimbabwe. In 2016, human water contact sites were identified in four communities in Madziwa area, Shamva district, Zimbabwe. The survey sites were recorded and mapped using a global positioning system. A 655 bp region of the mitochondrial cytochrome oxidase subunit I gene was amplified in 70 B. pfeifferi snails. The sequence data were analysed to determine the relationships between the individual snails, their inter, intra population diversity and structure. Overall, four unique cox1 haplotypes, with a haplotype diversity of 0.608, were identified in the snails. One haplotype spanned across most of the sites. There was no clear geographical clustering of haplotypes. The mean diversity among the haplotypes was very low (0.009), while the net divergence among the collection sites ranged from 0.000 to 0.026. The diversity within and between the sites was 0.017 and 0.012 respectively. This data advances our knowledge of the understanding of the population structure of B. pfeifferi in Madziwa area, Zimbabwe, with the high occurrence of one haplotype indicating the possibility of a recent bottleneck followed by population expansion. The population genetic structure of B. pfeifferi snails described here has provided an opportunity to investigate the contribution of snail genetics to variation in disease burden; and development of control strategies that exploit genetic differences in susceptibility to parasites.

Molecular diversity of Bulinus species in Madziwa area, Shamva district in Zimbabwe: implications for urogenital schistosomiasis transmission.

BACKGROUND: Bulinus species are freshwater snails that transmit the parasitic trematode Schistosoma haematobium. Despite their importance, the diversity of these intermediate host snails and their evolutionary history is still unclear in Zimbabwe. Bulinus globosus and B. truncatus collected from a urogenital schistosomiasis endemic region in the Madziwa area of Zimbabwe were characterized using molecular methods. METHODS: Malacological survey sites were mapped and snails were collected from water contact sites in four communities in the Madziwa area, Shamva district for a period of one year, at three-month intervals. Schistosoma haematobium infections in snails were determined by cercarial shedding and the partial mitochondrial cytochrome c oxidase subunit 1 gene (cox1) was used to investigate the phylogeny and genetic variability of the Bulinus spp. collected. RESULTS: Among the 1570 Bulinus spp. snails collected, 30 (1.9%) B. globosus were shedding morphologically identified schistosomes. None of the B. truncatus snails were shedding. The mitochondrial cox1 data from 166 and 16 samples for B. globosus and B. truncatus, respectively, showed genetically diverse populations within the two species. Twelve cox1 haplotypes were found from the 166 B. globosus samples and three from the 16 B. truncatus samples with phylogenetic analysis showing that the haplotypes fall into well-supported clusters within their species groups. Both B. truncatus and B. globosus clustered into two distinct lineages. Overall, significant negative values for both Tajima's D statistic and the Fu's Fs statistic were observed for B. globosus and B. truncatus. CONCLUSIONS: The study provided new insights into the levels of genetic diversity within B. globosus and additional information on B. truncatus collected from a small geographical area in Zimbabwe. Low prevalence levels of infection observed in the snails may reflect the low transmission level of urogenital schistosomiasis in the area. Our results contribute towards the understanding of the distribution and population genetic structure of Bulinus spp. supporting the mapping of the transmission or risk of transmission of urogenital schistosomiasis, particularly in Zimbabwe.